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Backport of Docs discovery typo into release/1.15.x #16633

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Backport of Docs discovery typo into release/1.15.x #16633

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backport of commit d663303e4b20636212ace9cad80fb1b671ce7a64
bdronneau Mar 14, 2023
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backport of commit f6d5cd04813072529e58415e39a6b3743f6ef90b
bdronneau Mar 14, 2023
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32 changes: 16 additions & 16 deletions website/content/docs/services/discovery/dns-dynamic-lookups.mdx
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Expand Up @@ -5,7 +5,7 @@ description: ->
Learn how to dynamically query the Consul DNS using prepared queries, which enable robust service and node lookups.
---

# Enable dynamic DNS aueries
# Enable dynamic DNS queries

This topic describes how to dynamically query the Consul catalog using prepared queries. Prepared queries are configurations that enable you to register a complex service query and execute it on demand. For information about how to perform standard node and service lookups, refer to [Perform Static DNS Queries](/consul/docs/services/discovery/dns-static-lookups).

Expand All @@ -20,7 +20,7 @@ If ACLs are enabled, the querying service must present a token linked to permiss

- [Prepared query rules](/consul/docs/security/acl/acl-rules#prepared-query-rules)
- [Service rules](/consul/docs/security/acl/acl-rules#service-rules)
- [Node rules](/consul/docs/security/acl/acl-rules#node-rules)
- [Node rules](/consul/docs/security/acl/acl-rules#node-rules)

## Create prepared queries
Refer to the [prepared query reference](/consul/api-docs/query#create-prepared-query) for usage information.
Expand All @@ -41,42 +41,42 @@ Refer to the [prepared query reference](/consul/api-docs/query#create-prepared-q
"Near": "node1",
"OnlyPassing": false,
"Tags": ["primary", "!experimental"],
"NodeMeta": {
"instance_type": "m3.large"
},
"ServiceMeta": {
"environment": "production"
}
"NodeMeta": {
"instance_type": "m3.large"
},
"ServiceMeta": {
"environment": "production"
}
},
"DNS": {
"TTL": "10s"
}
}
}
```

Refer to the [prepared query configuration reference](/consul/api-docs/query#create-prepared-query) for information about all available options.

1. Send the query in a POST request to the [`/query` API endpoint](/consul/api-docs/query). If the request is successful, Consul prints an ID for the prepared query.
1. Send the query in a POST request to the [`/query` API endpoint](/consul/api-docs/query). If the request is successful, Consul prints an ID for the prepared query.

In the following example, the prepared query configuration is stored in the `payload.json` file:

```shell-session
$ curl --request POST --data @payload.json http://127.0.0.1:8500/v1/query
{"ID":"014af5ff-29e6-e972-dcf8-6ee602137127"}%
```
1. To run the query, send a GET request to the endpoint and specify the ID returned from the POST call.
1. To run the query, send a GET request to the endpoint and specify the ID returned from the POST call.

```shell-session
$ curl http://127.0.0.1:8500/v1/query/14af5ff-29e6-e972-dcf8-6ee602137127/execute\?near\=_agent
```

## Execute prepared queries
You can execute a prepared query using the standard lookup format or the strict RFC 2782 SRV lookup.

### Standard lookup

Use the following format to execute a prepared query using the standard lookup format:

```
<query name or id>.query[.<datacenter>].<domain>
```
Expand All @@ -93,9 +93,9 @@ _<query name or id>._tcp.query[.<datacenter>].<domain>
For additional information about following the RFC 2782 SRV lookup format in Consul, refer to [RFC 2782 Lookup](/consul/docs/services/discovery/dns-static-lookups#rfc-2782-lookup). For general information about the RFC 2782 specification, refer to [A DNS RR for specifying the location of services \(DNS SRV\)](https://tools.ietf.org/html/rfc2782).

### Lookup options
The `datacenter` subdomain is optional. By default, the lookup queries the datacenter of this Consul agent.
The `datacenter` subdomain is optional. By default, the lookup queries the datacenter of this Consul agent.

The `query name` or `id` subdomain is the name or ID of an existing prepared query.
The `query name` or `id` subdomain is the name or ID of an existing prepared query.

## Results
To allow for simple load balancing, Consul returns the set of nodes in random order for each query. Prepared queries support A and SRV records. SRV records provide the port that a service is registered. Consul only serves SRV records if the client specifically requests them.
To allow for simple load balancing, Consul returns the set of nodes in random order for each query. Prepared queries support A and SRV records. SRV records provide the port that a service is registered. Consul only serves SRV records if the client specifically requests them.